Tug boat - lng barge system with an umbilical power line

ABSTRACT

The disclosure relates to a transport-cargo vessel system configured for travel on water. The vessel system either includes a tug boat section and a barge section configured to interlock. The barge section is configured to carry liquefied natural was (LNG) and includes an LNG electric generator. In some embodiments, the barge section is configured to carry LNG and at least one additional cargo. The additional cargo may include a cargo for resupplying another vessel. The tug boat includes a propulsion system with an electric motor configured to receive electric power generated from multiple fuels. Electricity from the barge&#39;s generator is provided to the tug boat&#39;s motor via a power umbilical line.

CROSS REFERENCE TO RELATED APPLICATION

This application claims the benefit of U.S. Provisional Patent Application No. 61/816,862 filed Apr. 29, 2013 and Non-Provisional patent application Ser. No. 13/944,291 filed Jul. 17, 2013, which applications are hereby incorporated by reference for all purposes in its entirety.

BACKGROUND OF THE DISCLOSURE

1. Field of Disclosure

The present disclosure relates to a tug-barge vessel system for transporting one or more of Liquefied Natural Gas (LNG), petroleum products, such as Marine Gas Oils (MGO), hydraulic fluids, distillate fuels, bio-fuels, lubricants, and water, and performing cargo delivery over water, and, in particular, on the ocean, lakes, bays, sounds and inland waterways. The tug-barge vessel system includes an umbilical line (or umbilical or umbilical cord) configured to supply electrical power to the main propulsion drive of the tug boat (or tug) from a generator on the barge while the tug and the barge are under weigh, at anchor, or in port. The umbilical line may also be configured to supply additional power for other electrical loads on the tug (hotel power, etc.).

2. Description of the Related Art

Cargo, such as LNG, may be transported across the sea and along inland waterways using specially designed water-going vessels, including, self-propelled, vessels and barge that may be combined tugs (such as an Integrated Tug-Barge (ITB) or an Articulated Tug-Barge (ATB)). Typically, LNG transport vessels are designed to carry LNG (for hire by others) as their sole cargo. Thus, an LNG transport vessel is unable to resupply another vessel with non-LNG supplies, such as MGO, hydraulic fluids, distillate fuels, bio-fuels, lubricants, and water. One or more additional vessels, truck's or other delivery methods are required to supply a vessel with non-LNG supplies.

Typically LNG transport vessels are designed to be compliant with regulations for their transport medium. LNG transport vessel may be designed for compliant operation as sea-going vessels or as inland waterway vessels.

Substantial cost is incurred by using two vessels to resupply a vessel in need of LNG and additional supplies. Involving two resupply vessels with a vessel to be resupplied requires coordination and timing, of the resupply operation to prevent downtime and avoid conflicts. What is needed is a single vessel that can resupply the needs of the vessel requiring, resupply. Additionally, most LNG transport vessels are designed for operation at sea. What is needed is a LNG transport vessel that is configured to deliver various cargos for both sea-going, lakes, bays, sounds and inland waterway operation.

Furthermore, the tug boat's propulsion systems typically comprise of a diesel engine, wherein the tug boat includes on-board storage for diesel fuel. A need exists for the tug boat's propulsion system to operate using electric power derived from more than one power source. What is further needed is a LNG electrical generator on a barge to supply power to the tug boat's propulsion system.

BRIEF SUMMARY OF THE DISCLOSURE

In aspects, the present disclosure is related to a system and method of providing electrical power to a tug boat's propulsion system, and, in particular, providing the electrical power from a barge, wherein the barge includes an electrical generator that uses LNG as a fuel. The barge can be configured to include LNG storage tanks for the transport of LNG fuel for others. The electrical generator can also be configured for dual fuel operations using LNG and switchable to another fuel, such as diesel fuel or CNG.

One embodiment according to the present disclosure includes a tug and a barge, wherein the barge is configured to carry LNG and a resupply cargo and wherein the tug boat and the barge are configured to interlock. The LNG may be stored in at least one of: a tank integrated into the hull of the barge and a non-integrated tank. The resupply cargo may include at least one of: i) MGO, ii) hydraulic fluid, iii) bio-fuel, iv) lubricant, v) distillate fuel, and vi) water. The barge may be configured to meet certification requirements for operation on at least one of: i) high seas, ii) U.S. inland waterways, iii) foreign inland waterways, iv) U.S. ports, and v) foreign ports. The barge is configured to resupply a marine vessel. The resupply configuration may include at least one of: bunkering, re-provisioning, and midstream refueling under weigh or at anchor. The barge may include a crane configured to move the resupply cargo. The tug boat's propulsion system is comprised of one or more main propulsion electric motors and one or more propulsion units that are driven by the one or more main propulsion electric motors. The tug boat's main propulsion electric motors are configured to receive power from at least one of: i) an LNG electric generator on the barge and ii) a diesel electric generator located on the barge or the tug. The propulsion system may be configured to switch to diesel electric generator when LNG electricity generation is unavailable. The tug includes a storage tank for the diesel fuel needed fur the tug's diesel generator operations. The barge includes a LNG powered electric generator. LNG from one of the barge's LNG storage tank supplies LNG fuel to the LNG powered electric generator. An umbilical line is provided to transmit electrical power from the LNG powered electric generator to the tug boat's electrical system for distribution to the tug boat's electric propulsion system. The umbilical line may be stored on the tug or barge for easy installation or removal.

Another embodiment according to the present disclosure includes a system for supplying electrical power from a first marine vessel to a second marine vessel, comprising: an LNG fuel tank and an LNG-fueled electric generator on the first marine vessel; an electric motor configured to provide propulsion for the second marine vessel, and an electrical umbilical coupled between the LNG-fueled electric generator and the electric motor. The electric generator may be coupled with a non-propulsion electrical system of the tug boat. The first marine vessel may be a barge and the second marine vessel may be a tug boat. The barge may include a hull comprising at least one integrated storage tank configured to hold at least one of: a resupply cargo and LNG. The at least one integrated tank may include a first tank for the resupply cargo and a second tank for the LNG. The first marine vessel may be configured to resupply a third vessel. The configuration for resupply may include configuration for at least one of: bunkering, re-provisioning, and midstream refueling. The barge may include a crane configured to move the resupply cargo. The resupply cargo may include at least one of: i) MGO, ii) hydraulic fluid, iii) bio-fuel, iv) lubricant, v distillate fuel and vi) water. In some aspects the barge may include a non-hull integrated tank configured to hold a resupply cargo. The barge may be configured to satisfy at least one of: meeting certification requirements for operation on at least one of: i) high seas, ii) U.S. inland waterways, iii) foreign inland waterways, iv) U.S. ports, and v) foreign ports.

Another embodiment according to the present disclosure includes a method of providing electrical power to a second marine vessel from a first marine vessel, the method comprising steps of: generating electricity on the first marine vessel using an LNG-fueled electric generator disposed on the first marine vessel; and providing the generated electricity to an electric motor configured for propulsion on the second marine vessel, wherein the electricity is provided using a power umbilical. The first marine vessel may comprise a barge configured to carry LNG fuel and a cargo. The cargo may include LNG and a resupply cargo. The resupply cargo may include at least one of: i) MGO, ii) hydraulic fluid, iii) bio-fuel, iv) lubricant, v) distillate fuel, and vi) water. The method may also include at step of: moving at least part of the resupply cargo from the first marine vessel to the second marine vessel using a crane. The crane may be mounted on the first marine vessel. The step of moving the at least pan of the resupply cargo may include pumping the at least part of the resupply cargo from a non-integrated tank on the first marine vessel to a tank disposed on the second marine vessel.

BRIEF DESCRIPTION OF DRAWINGS

For a detailed understanding of the present disclosure, reference should be made to the following detailed description of the embodiments, taken in conjunction with the accompanying drawings, in which like elements have been given like numerals, wherein:

FIG. 1 shows a three-dimensional view of a versatile transport-delivery vessel according to one embodiment of the present disclosure;

FIG. 2 shows a side view of the versatile transport-delivery vessel of FIG. 1;

FIG. 3 shows a view of the versatile transport-delivery vessel of FIG. 1 from the tug boat side;

FIG. 4 shows a view of another versatile transport-delivery vessel according to one embodiment of the present disclosure;

FIG. 5 shows a view of the barge of FIG. 1 from the recessed notch coupling side;

FIG. 6A shows a schematic of the barge of FIG. 1 from the topside;

FIG. 6B shows a schematic of the barge of FIG. 1 from the side;

FIG. 6C shows a schematic of the barge of FIG. 1 from the front;

FIG. 7 shows a cutaway view of the barge of FIG. 1;

FIG. 8 shows a schematic of the tug and barge with a power umbilical according to one embodiment of the present disclosure;

FIG. 9A shows a top view of the barge with an umbilical mounting according to one embodiment of the present disclosure;

FIG. 9B shows a side view of the barge with an umbilical mounting according to one embodiment of the present disclosure;

FIG. 10A shows a side view of the tug boat with a power input for receiving a power umbilical according to one embodiment of the present disclosure;

FIG. 10A shows a side view of the tug boat with a power input for receiving a power umbilical according to one embodiment of the present disclosure;

FIG. 10B shows a deck plan of a level of the tug wherein the power input located according to one embodiment of the present disclosure; and

FIG. 10C shows a deck plan of a machinery space the tug boat wherein the electricity from the power umbilical is distributed to the propulsion system of the tug boat according to one embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE DISCLOSURE

Generally, the present disclosure relates to a water-going vessel for transporting LNG and, optionally, at least one other cargo. Specifically, the present disclosure is related to transporting LNG and optionally, at least one other cargo, where the vessel is a barge configured to interlock with a tug boat, and where the cargo is a material required for resupply of a water-going vessel. The novel vessel is configured for “bunkering” operations (such as the resupply of consumables, fuel for propulsion or auxiliaries (e.g., generators)) to other vessels under weigh, at anchor, or in port. In addition, the vessel is configured for “re-provisioning” to other vessels for MGOs, hydraulic fluids, distillate fuels, bio-fuels, lubricants, water, stores or groceries. The vessel may be configured for performing “midstream fueling,” provisioning of engineering equipment and supplying “stores” for other consumables when operating on inland waters or high seas or other suitable locations as would be understood by a person of ordinary skill in the art with the benefit of the present disclosure. The present disclosure is susceptible to embodiments of different forms. There are shown in the drawings, and herein will be described in detail, specific embodiments of the present disclosure with the understanding that the present disclosure is to be considered an exemplification of the principles of the present disclosure and is not intended to limit the present disclosure to that illustrated and described herein.

A versatile transport-delivery vessel may be configured for operation on water to transport LNG and to deliver supplies as additional cargo. The additional cargo is configured for at least one of: bunkering, re-provisioning, and midstream fueling of another vessel as would be understood by a person of ordinary skill in the art with the benefit of the present disclosure. The versatile transport-delivery vessel may include one or more LNG tanks and one or more additional tanks configured to carry the additional cargo. The cargo may be stored in one or more tanks or compartments. The one or more of the tanks may be integrated with the hull of the versatile transport-delivery vessel. One or more of the tanks may be separate from the hull. In some embodiments, the additional cargo may be resupply cargo. Herein, “resupply cargo” is cargo that is used for resupplying operational consumables in a lake, sound, bay, inland or ocean going vessel. For instance, resupply cargo may include, but is not limited to, one or more of MGO, hydraulic fluids, distillate fuels, bio-fuels, lubricants, and water.

The versatile transport-delivery vessel ma include a barge section and a tug section. Each of the two sections may be configured to mate with the other to form a locking connection. Other configurations, such as a self-propelled single vessel is also contemplated. In the tug barge configuration, the locking connection may be rigid (as in ITBs) or allow for some movement (as in ATBs or Push Boat & Barge or Tug and barge on tow line). The preferred embodiment is an ATB configuration. Both of the sections may be configured to comply with Det Norske Veritas (DNV) certification (or other Classification Societies), Jones Act or other international requirements (such International Maritime Organization—IMO or Safety of Life at Sea—SOLAS) for water vessels. Both of the sections may also be configured with a fully loaded draft that is compliant with inland waterway requirements. In some embodiments, the fully loaded draft of the sections is at or under 9 feet and 6 inches. The LNG transport-delivery vessel may be configured to comply with overall length, beam, and channel requirements for transit on U.S. Inland and International Waterways (including, but not limited to, GIWW, Mississippi River, Ohio River and Panama Canal/Suez Canal). The overall length and beam are configured for transit through lock structures, bridges, overhangs and channels along U.S. Inland Waterways. The LNG transport-delivery vessel may have an aerial, draft that is under the lowest aerial clearances for GIWW, Mississippi River, Ohio River and Panama Canal/Suez Canal).

FIG. 1 shows a versatile transport-delivery vessel 100 according to one embodiment of the present disclosure. The vessel 100 may include a tug boat 140 and a barge 105. The barge 105 may have a first end 101 and a second end 102. The tug boat 140 may have a first end 141 and a second end 142, where the first end 141 is configured to interlock with the barge 105. The second end 102 of the barge 105 may include a notch coupling, such as recessed area 110, so that the barge 105 is configured to receive the first end 141 of the tug boat 140. The recessed area 110 may be shaped and form arms 120 on either side of the recessed area 110 on the second end 102. The arms 120 may include attachment mechanisms 130 for interlocking the tug boat 140 and the barge 105. The attachment mechanism 130 may comprise connection notches at the second end 192 of the barge 105 configured to receive corresponding connecting wedges (not shown) at the first end 141 of the tug boat 140. The use of notches and wedges as the attachment mechanism 130 is illustrative and exemplary only, as other suitable means known to a person of ordinary skill in the art may be used, including, but not limited to, one or more of: wire, chains, and rope. The attachment mechanism 130 may be configured for at least one of an articulated connection and a rigid connection between the barge 105 and the tug boat 140. The tug boat 140 is configured to propel the barge 105 while the tug boat 140 and barge 105 are interlocked. The tug boat 140 can be configured for push/pull operations. The tug boat 140 may be configured to pull the barge 105 when the tug boat 140 is disengaged from attachment means 130.

The barge 105 may include a hull 115 with an upper deck 117. The barge 105 may also include one or more tanks 150 configured to store and transport LNG. In some embodiments, the tanks 150 may be integrated into the hull 115 of the barge 105. In some embodiments, the tanks 150 may be positioned in the hull 115 by saddles (e.g., U-supports) or membranes (not shown). In some embodiments, the tanks 150 may protrude above the level of the upper deck 117. The barge 105 may also include one or more compartments 160 for storing additional cargo. The compartments 160 may include tanks or enclosed containers (such as Marine Portable Tanks). In some embodiments, the compartments 160 may be integrated into the hull 115. In some embodiments the additional cargo may be stored in tanks 180 that are not integrated into the hull 105. In the preferred embodiment, the barge 105 may also include one or more service cranes 170. The crane 170 may be configured for moving cargo or lifting doors to deck hatches.

FIG. 2 shows the vessel 100 from FIG. 1 from the side. The tug boat 140 may include a propulsion system including a propulsion unit 210. In some embodiments, the propulsion system may include one or more of: three propellers, a ducted propeller (such as a KORT nozzle), and azimuth thrusting propulsion pods. The tug boat 140 may also include a rudder 220. Herein, the tug boat 140 is shown with a draft 146 that is substantially similar to a draft 106 of the barge 105. In some embodiments, the draft 146 and the draft 106 may he different depending in conditions (ocean or inland operation). FIG. 3 shows a view of the vessel 100 from FIG. 1 from the tug boat 140.

FIG. 4 shows a versatile transport-delivery vessel 400 according to another embodiment of the present disclosure. The vessel 400 may be self-propelled and have a first end 401 and a second end 402. The vessel 400 may include a hull 415 with an upper deck 417. The vessel 400 may also include one or more tanks 150 configured to store and transport LNG. In some embodiments, the tanks 150 may be integrated into the hull 415 of the vessel 400. In some embodiments, the tanks 150 may be positioned in the hull 415 by saddles (e.g., U-supports) or membranes (not shown). In some embodiments, the tanks 150 may protrude above the level of the upper deck 417. The vessel 400 may also include one or more compartments 460 for storing additional cargo. The compartments 460 may include tanks or enclosed containers (such as Marine Portable Tanks). In some embodiments, the compartments 160 may be integrated into the hull 415. In the preferred embodiment, the vessel 400 may also include one or more service cranes 170. The crane 170 may be configured for moving cargo or lifting doors to deck hatches.

FIG. 5 shows the barge 105 from FIG. 1 viewed mostly from the second side 102. The recessed area 110 is shown as a substantially smooth U-shape. The smooth U-shape is exemplary and illustrative only, as any shape for the recessed area 110 so long at the front end 141 of the tug boat 140 may be received and the tug boat 140 interlocked with the barge 105 at attachment mechanism 130.

FIG. 6A shows a top view of barge 105 from FIG. 5. As shown, the barge 105 includes two tanks 150 for storing LNG disposed on each side (port and starboard) of the barge 105. This distribution of the tanks 150 is exemplary and illustrative only, as the tanks 150 may be distributed in any manner (i.e. fore and aft, etc.). In some embodiments, the tanks 150 are integrated with the bull 115. The number of tanks 150 is shown as two, however, more than two tanks 150 may be included in barge 105. In some embodiments, a single tank 150 may be disposed on the barge 105. The additional cargo containment 160 may include one or more tanks or compartments. As shown here, the additional containment 160 may be integrated into the hull 115. In sonic embodiments, the containment 160 may include one or more of MGO, hydraulic fluids, distillates, bio-fuels, lubricants, and water. Here, the containment 160 includes a port MGO tank 163 p, a starboard MGO tank 163 s, a port fuel oil tank 165 p, and a starboard fuel oil tank 165 s. FIG. 6B shows a side view of barge 105 from FIG. 5. FIG. 6C shows a front view of barge 105 from FIG. 5.

FIG. 7 shows a cutaway view showing the starboard side of the barge 105. The starboard fuel oil tank 165 s and the starboard MGO tank 163 s are shown integrated in hull 115 below the level of the deck 117 near the recessed area 110. The location of the additional cargo compartments 160 near the second end 102 is exemplary and illustrative only, as the additional cargo compartments 160 may be located anywhere on or in the barge 105.

In operation, the additional cargo stored in the compartments 160 or non-integrated tanks 180 may be moved from the vessel 100, 400 to a second marine vessel. The additional cargo may be moved by pumping of the additional cargo (if pumpable) through umbilicals or hoses between the marine vessels, by crane offloading, or by manual offloading of the additional cargo as would be understood by as person of ordinary skill in the art.

FIG. 8 show a tug barge vessel system 800 system according to another embodiment of the present disclosure. The system 800 may includes a tug boat 140 and a barge 105 in an ATB configuration. The tug boat 140 may power its electric motors with electric, power from a diesel electric generator 840 disposed on the tug 140 or from electric power produced on the barge 105. The barge 105 may include an LNG-fueled electric generator 810. The LNG-fueled electric generator 810 may receive LNG from a fuel tank 820 disposed on the barge 105. The fuel tank 820 may be disposed separate from or adjacent to the cargo containment area 860 of the barge 105. If the cargo containment area 860 is configured to carry LNG, then LNG tanks 150 may be disposed in the cargo containment area 860. In some embodiments, additional piping and valving may be configured to allow LNG from at least one LNG tank 150 to supply LNG to the fuel tank 820 or to supply LNG directly to the LNG-fueled electric generator 810.

In some embodiments, the LNG-fueled electric generator 810 may operate using LNG that has been converted to Compressed Natural Gas (CNG). The fuel tank 820 may be configured to store and dispense CNG to the electric generator 810. The fuel tank 820 at d suitable valving/compression equipment may be configured to receive LNG from the LNG tank 150 and store the LNG in the form of CNG in the fuel tank 820, which is, in turn, supplied, to the electric generator 810.

Electric power generated by the LNG-fueled electric generator 810 may be communicated to the electric motors of the tug boat 140 through one or more power umbilicals 830. The power umbilical 830 may be any cable configured to communicate electrical power. The power umbilical 830 may be insulated against water, moisture, temperature, physical impact, and corrosion. Since the tug boat 140 and the barge 105 will have sonic independence of motion relative to one another, the power umbilicals 830 may be configured with protection against strain imposed by the relative motion of the tug boat 140 and the barge 105. The power umbilical 830 ma be reinforced to prevent breakage or severance. Each power umbilical 830 may be a single cable or may be made up of two or more attachable/detachable segments. The power umbilicals 830 may include special quick disconnects that are configured to allow emergency separation of the vessels without damage to the power umbilicals 830. In some embodiments, the power umbilical 830 may be configured to prevent contact between the electric power and the environment in the even that the power umbilical is detached or severed while the LNG-fueled electric generator 810 is transmitting electric power. In some embodiments, the system 800 may be equipped with a switching device (not shown) that automatically switches the propulsion system on the tug 140 from attempting to draw power from the power umbilicals 830 to drawing power from the diesel electric generator 840 in the event that the power coining over the power umbilicals 830 is interrupted.

The power umbilicals 830 may be disposed to transmit power to the power output of the diesel generator 840 to the propulsion system motors of the tug boat 140 so as to minimize the number of connection points to the propulsion motors for incoming electric power. Thus, the propulsion system of the tug boat 140 may be powered from the diesel generator 840 on the tug boat 140 or from the LNG-fueled electric generator 810 on the barge 105. In some embodiments, the propulsion system of the tug boat 140 may even be powered from a diesel generator (not shown) on the barge 105. The power umbilicals 830 may be dimensioned to reduce power losses, voltage losses, and physical size (cross-sectional area, thickness, length, etc.) as would be understood by a person of ordinary skill in the art with the benefit of the present disclosure. In some embodiments, the power from the LNG-fueled electric generator 810 may be stepped up at the barge 105 for transmission through the power umbilical 830 and stepped down on the tug 140.

As shown in FIG. 8, two power umbilicals 830 may be disposed on the port and starboard sides of the barge 105. The use of dual power umbilicals spaced on either side of the barge is exemplary and illustrative only, as other numbers of power umbilicals and positions may be used as would be understood by a person of ordinary skill in the art.

Also as shown in FIG. 8, the power umbilicals 830 may be configured to communicate power from the barge 105 that is adjacent to the tug boat 140. This is also exemplary and illustrative only, as the tug, boat 140 may be configured to provide propulsion to multiple barges. In the event that multiple barges are used, a barge (not shown) that is not adjacent to the tug boat 140 may be configured to venerate electric power for the tug boat 140 and may communicate the electric power to the barge 105 over another set of power umbilicals.

In some embodiments, the electric power for non-propulsion systems of the tug boat 140 may be configured to be powered by, alternately, the LNG-fueled generator 810 and the diesel generator 840.

FIGS. 9A and 9B show views of the barge 105 according to another embodiment of the present disclosure. FIG. 9A shows a top view of the barge 105 including the umbilical mountings 900 (which enclose power umbilicals 830), where the umbilical mountings 900 are disposed on the arms 120 at the second end 102 of the barge 105. FIG. 9B shows a profile view of the barge 105 from the port side, also including the umbilical mounting 900 on the port side.

FIGS. 10A, 10B, and 10C show views of the tug boat 140 configured to mate with the barge 105 of FIGS. 9A and 9B according to one embodiment of the present disclosure. FIG. 10A shows a side view of the tug boat 140 including the power input 1000 for the power umbilical 830 on the port side of the tug boat 140. FIG. 10B shows a top view of the level 1010 of the tug boat 140 where the power input 1000 is located on the port side of the tug boat 140. As shown, power inputs 1000 are disposed on the port and starboard sides of level 1010; however, this is illustrative and exemplary only, as there may be one or more power inputs and they may be disposed in any suitable location to provide power to the tug 1.40. FIG. 10C shows a top view of the machinery space level 1020 of the tug boat 140, wherein the electricity from the power umbilicals 830 is directed to the propulsion system of the tug boat 140. The propulsion system may include a power switchboard 1030 that configured to distribute electricity from the power umbilicals 830 to electric motors 1040 that drive the propulsion units 210 of the tug boat 140. The power switchboard 1030 may also distribute power to non-propulsion systems circuits 1050. As shown, diesel electric generators 840 disposed in the machinery space 1020 and may be configured to deliver electricity to the power switchboard 1030 as well. While the diesel electric generators 840 are shown as an alternate power source for the propulsion units 210, this is exemplary and illustrative only, as it is contemplated that any non-LNG-fueled electric generator may be used to supply alternate power to the propulsion units 210.

While the disclosure has been described with reference to exemplary embodiments, it will be understood that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the disclosure. In addition, many modifications will be appreciated to adapt a particular instrument, situation or material to the teachings of the disclosure without departing from the essential scope thereof. Therefore, it is intended that the disclosure not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this disclosure, but that the disclosure will include all embodiments falling, within the scope of the appended claims. 

What is claimed is:
 1. A system for supplying electrical power from a first marine vessel to a second marine vessel, comprising: an LNG fuel tank and an LNG-fueled electric generator on the first marine vessel; at least one electric motor configured to provide propulsion for the second marine first marine vesselvessel, and an electrical umbilical coupled between the LNG-fueled electric generator and the electric motor.
 2. The system of claim 1, further comprising: a non-LNG-fueled electric generator configured as an alternative power supply for the at least one electric motor.
 3. The system of claim 2 wherein the non-LNG-fueled electric generator is disposed on the first marine vessel.
 4. The system of claim 2, wherein the on-LNG-fueled electric generator is disposed on the second marine vessel.
 5. The system of claim 2, wherein the non-LNG-fueled electric generator is a diesel electric generator.
 6. The system of claim 1, wherein the first vessel is a barge and the second marine vessel is a tug boat.
 7. The system of claim 6, wherein the barge comprises: a hull; and wherein the hull comprises at least one integrated tank configured to hold at least one of: a resupply cargo and LNG.
 8. The system of claim 7, wherein the first marine vessel is configured to resupply a third vessel.
 9. The system of claim 8, wherein configuration to resupply includes configuration for at least one of: bunkering, re-provisioning and midstream refueling.
 10. The system of claim 7, further comprising: a crane configured to move the resupply cargo.
 11. The system of claim 7, wherein the at least one integrated tank comprises a first tank configured to hold a resupply cargo and a second tank configured to hold LNG.
 12. The system of claim 7, wherein the resupply cargo includes at least one of: i) MGO, ii) hydraulic fluid, iii) bio-fuel, iv) lubricant, v) distillate fuel, and vi) water.
 13. The system of claim 6, wherein the barge comprises: a hull; and at least one non-hull integrated tank configured to hold a resupply cargo.
 14. The system of claim 6, wherein the barge is configured to meet certification requirements for operation on at least one of: i) high seas, ii) U.S. inland waterways, iii) foreign inland waterways, iv) U.S. ports, and v) foreign ports.
 15. The system of claim 6, wherein the barge is dimensioned for travel on U.S. inland waterways.
 16. The system of claim 6, wherein the electric motor is coupled to a non-propulsion electrical system.
 17. The system of claim 6, wherein the barge and the tug boat form an articulated tug-barge.
 18. The system of claim 1, wherein the at least one electric motor comprises: three electric motors; and further comprising: three propulsion units disposed on the second marine vessel; wherein each is the three electric motors corresponds to one of the three propulsion units and is configured to supply mechanical power to the corresponding propulsion unit.
 19. A method of providing electrical power to a second marine vessel from a first marine vessel, the method comprising steps of: generating electricity on the first marine vessel using an LNG-fueled electric generator disposed on the first marine vessel; and providing the generated electricity to at least one electric motor configured for propulsion on the second marine vessel, wherein the electricity is provided using a power umbilical.
 20. The method of claim 19, further comprising: providing electricity to the at least one electric motor using a non-LNG fueled electric generator when the generated electricity from the LNG fueled electric generator is not available.
 21. The method of claim 20, wherein the non-LNG-fueled electric generator is disposed on the first marine vessel.
 22. The method of claim 20, wherein the non-LNG-fueled electric generator is disposed on the second marine vessel.
 23. The method of claim 20, wherein the non-LNG-fueled electric generator is a diesel electric generator.
 24. The method of claim 19, wherein the first marine vessel comprises a barge configured to carry LNG fuel and a cargo.
 25. The method of claim 24, wherein the cargo comprises LNG and a resupply cargo.
 26. The method of claim 25, wherein the resupply cargo comprises at least one of i) MGO, ii) hydraulic fluid, iii) bio-fuel, iv) lubricant, v) distillate fuels, and vi) water.
 27. The method of claim 25, further comprising a step of: moving at least part of the resupply cargo from the first marine vessel to the second marine vessel using a crane.
 28. The method of claim 27, wherein the crane is mounted on the first marine vessel.
 29. The method of claim 27, wherein moving the at least part of the resupply cargo comprises: pumping the at least part of the resupply cargo from a non-integrated tank on the first marine vessel to a tank disposed on the second marine vessel. 